PURPOSE: This study was performed to evaluate the surgical and the oncological outcomes of preoperative radio-chemotherapy (PRCT) in patients with low rectal cancer. METHODS: We reviewed 26 (M:F=17:9) patients who underwent PRCT between September 1999 and December 2001. Inclusion criteria were lower rectal cancer (4~5 cm from AV), more than T3 or N1 in preoperative staging using CT scan and transrectal ultrasound, and no distant metastasis. Patients received a mean of 47.3 (45.0 ~56.0) Gy of radiation therapy for 5 weeks and concomitant intravenous or oral chemotherapy using 5 FU and leucovorin. Surgery was performed in about 5~6 weeks after completion of radiotherapy. Total mesorectal excision and autonomic nerve preservation was the routine procedure. Adverse events during PRCT were assessed according to the NCI Common Toxicity Criteria (version 2.0, 1997). RESULTS: The mean age was 49 (28~65) years old. The median follow-up period was 31 (20~44) months. The most frequent adverse event was diarrhea (8, 30.8%), followed by nausea and vomiting (5, 19.2%), dermatitis (5, 19.2%), anemia (4, 15.4%), leucopenia (2, 7.7%), and mucositis (1, 3.8%). The mean location of the tumor was elevated from 4.5 cm to 5.5 cm after PRCT. Downstaging of the tumor was identified in 69.2% of the T-level and 63.2% of the N-level. The serum CEA level was decreased from 14.5+/-5.0 ng/ml to 3.5+/-0.5 ng/ml after PRCT (P=0.034). A sphincter-saving resection (SSR) was possible in 16 cases (61.5%). The mean distal resection margin was 2.2+/-0.7 cm in SSRs. Small bowel obstruction was the most frequent complication (6 cases, 23.1%), followed by hydronephrosis 2 (7.7%), a recto-vaginal fistula (1, 3.8%), and a recto-vesical fistula (1, 3.8%). There were no mortalities. Five (19.2%) recurrences developed in distant area, one (3.8%) in a local area, and one in both a local and a distant area. The patients with N-level downstaging revealed a significantly low recurrence rate (8.3% vs. 57.1%; P=0.03). CONCLUSIONS: PRCT can be performed with an acceptable toxicity and complication rate. It is effective in downstaging of the tumor and in increasing the sphincter-saving rate. However, a prospective, randomized, controlled trial should be performed to prove the oncological benefit.